In some network environments, an intermediary device may be deployed between a client and a server, such as inline to network traffic communicated between the client and the server. The intermediary device may perform functionality on network packets traversing the device as they are transmitted between the client and the server. The intermediary device may include one or more applications, programs or drivers to process network packets and to provide some form of value or improvement to the network communications, such as traffic management, firewall functionality or acceleration.
These network packet processing devices may operate at different levels of the network stack depending on the provided functionality. One type of such a device may intercept network communications at one layer of the network stack, such as the data link layer in a TCP/IP network stack. For example, a WAN acceleration device may transparently intercept, process and forward network communications between a client and a server at layer 2 of the network stack. Another type of device may intercept network communications at another layer of the network stack, such as the network layer or IP layer in a TCP/IP network stack. For example, a security gateway device may intercept network packets at layer 3 of the network stack and apply one or more policies to the network packet. The functionality of these devices operating at different layers of the network may not be interoperable.